after I hired someone, a mutual friend told me I’d made a huge mistake

This post was written by Alison Green and published on Ask a Manager .
A reader writes:
I made a pretty big hiring mistake and I’m not really sure how to proceed.
I recently hired a new employee — let’s call him Julian — for a fairly niche role within my company. Julian’s background aligned wgell with the role, all communication was timely and professional, he gave polished first and second interviews, and his salary ask was exactly to budget. He seemed like the perfect candidate.
Minutes after I sent Julian his offer letter, I got an unrelated call from a friend — let’s call him Pete — who wanted to catch up. Pete and Julian and I all used to work in the same industry. Pete and Julian worked for the same company at one point, though it was highly unlikely they would’ve known each other because Pete was working at the corporate office doing X and Julian was at a worksite doing Y.
When Pete asked how things were going at work, I responded with, “Great now that I just extended an offer to a candidate for X.” I then mentioned how Julian was also a veteran of our former field.
“Shot in the dark,” I went, “but you don’t happen to know Julian do you? He used to work at your former company.”
Pete cursed and went, “Why didn’t you call me before you extended that offer? I do know Julian. He was a nightmare!” Pete then asked if it was too late to pull the offer — it was.
Pete then told me how he personally had to go to Julian’s worksite to fire and escort him off the premises because there had been multiple reports of Julian acting erratically — like, having screaming matches with himself — and making female coworkers feel unsafe. Pete said his former company offered Julian both mental health and substance abuse counseling before letting him go, but Julian refused both offers.
I did call Julian’s references before hiring him. He did not provide a reference for his last position, but I didn’t question it because his other references were good.
Presently, Julian’s completed two days of training with me and has had zero issues.
I just don’t know what to do with the information that Pete gave me. Do I bring up my conversation with Pete to Julian? And am I obligated to bring this information to my boss? If Julian got the help he needed, I’m sure he’d also like to move on from that experience.
At this point, I’d do nothing with the information. You’ve hired him, his other references were good, and you’re not seeing problems so far.
What Pete told you is alarming, but it’s not easily actionable now that you’ve hired him. It would be different if you’d learned something that you absolutely had to dig into — like that Julian forged the license his job requires, or he fabricated significant information about his work history or skills. But that’s not really this. Making coworkers feel unsafe is a big deal and I don’t mean to minimize that … but it sounds very possible that he had a mental health crisis that could have since been resolved.
(It’s also possible that Pete’s information isn’t accurate, although it sounds like he has firsthand knowledge and presumably no reason to lie to you.)
Of course, there’s also a chance that the issues Pete saw are ongoing and will show up sooner or later. So you should be sure to pay enough attention that you’ll be able to catch any problems early, which should include checking in on how things are going with people who are working with him. Frankly, you should always do that with any new employee, and this is no different! But having Pete’s info gives you some context so you’ll be able to act more decisively if you do see or hear concerning things. Otherwise, if you hadn’t heard from Pete but started to have concerns about Julian, you might wonder if something had been misinterpreted or otherwise second-guess yourself; with Pete’s background info, you’ll presumably feel more confident intervening earlier if you need to. (That doesn’t mean you should approach Julian with suspicion! But use this as additional impetus for the work you should always do to ensure you know how things are going with a new hire.)
As for whether to share what Pete said with your boss … I’m leaning toward no. It risks biasing her against Julian when there may be no issues at all. But if you do start seeing problems, it makes sense to raise it at that point so that she’s able to assess things through the same lens as you.
For now, though, since Julian is already working for you, give him the benefit of the doubt that he’s moved on from whatever went wrong when he worked with Pete. If it turns out he hasn’t, you can be prepared to act.
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